Location based services (LBS) are emerging as a new type of value-added service provided by mobile or wireless communication network service providers. LBS are mobile services in which the location information of mobile devices is used in order to enable various LBS applications such as, for example, enhanced 911 (E-911), location-based 411, location-based messaging and/or local restaurants finding. A position of a mobile device is determined by using, for example, satellite-based systems such as global navigation satellite systems (GNSSs) such as, for example, the global positioning system (GPS), the GLobal NAvigation Satellite System (GLONASS), and the satellite navigation system GALILEO.
A GNSS utilizes an earth-orbiting constellation of a plurality of GNSS satellites each broadcasting GNSS signals which indicates its precise location and ranging information. From any location on or near the earth where the satellites may be visible, a GNSS enabled mobile device may detect GNSS signals and take various GNSS measurements such as pseudorange, carrier phase, and/or Doppler to calculate corresponding navigation information such as a position fix, velocity, and time. The GNSS enabled mobile device utilizes the calculated navigation information for various LBS applications such as E911, location-based 411, location-based messaging and/or friend finding. The LBS applications may be realized using various wireless and/or wired communication networks such as, for example, WCDMA, UMTS, HSDPA, CDMA, EV-DO, GSM, GPRS, EDGE, EGPRS, LTE, short-range wireless (Bluetooth), WiMAX, high-speed wireless LAN (WiFi), and/or wired Internet protocol (IP) networks.
Further limitations and disadvantages of conventional and traditional approaches will become apparent to one of skill in the art, through comparison of such systems with the present invention as set forth in the remainder of the present application with reference to the drawings.